In order to record information on optical discs, the write strategies used in recording must be optimally adjusted to the characteristics of the optical discs; an optical recording device generally holds an optimal write strategy for each optical disc ID (identification information) and uses the optimal write strategy in recording.
When the optimal write strategy specific to an optical disc is used in this way, however, recording cannot always be performed with good recording quality, because of the individual variability of the optical disc or the optical recording device. Another problem has been that recording quality may be lowered due to large optical disc warpage, non-uniform recording characteristics, or temperature changes during recording.
One countermeasure is to temporarily suspend recording and adjust or optimize the write strategy when the temperature changes or the recording speed changes, or at prescribed intervals (see Patent Documents 1 to 4, for example). In another known method, every time a prescribed amount of information is written on an optical disc, a first recording pulse pattern corresponding to the ambient temperature and a second recording pulse pattern corresponding to an altered temperature in the vicinity of the ambient temperature are read, information is written on the optical disc with both recording pulse patterns, and then whichever one of the first and second recording pulse patterns produces information having the lower error rate is selected as the recording pulse pattern for further writing (Patent Document 5). Another method is also known in which a plurality of adjustment amounts are prestored for each temperature parameter, and an adjustment amount corresponding to the temperature near the optical head is selected.
Patent Document 1: Japanese Patent Application Publication No. 2006-302332 (pp. 1-18, FIGS. 1-16)
Patent Document 2: Japanese Patent Application Publication No. 2007-200389 (pp. 1-20, FIGS. 1-16)
Patent Document 3: Japanese Patent Application Publication No. 2007-200435 (pp. 1-9, FIGS. 1-9)
Patent Document 4: Japanese Patent Application Publication No. 2007-213674 (pp. 1-9, FIGS. 1-5)
Patent Document 5: Japanese Patent Application Publication No. 2007-234188 (pp. 1-13, FIGS. 1-7)
Patent Document 6: Japanese Patent Application Publication No. 2007-273021 (pp. 1-11, FIGS. 1-13)